Technical Field
1. Field of the Invention:
The present invention relates to a horizontal revolute robot small-sized, light in weight, enjoying a wide range of action, and low-priced.
2. Description of the Related Art:
It is generally known to employ a cylindrical coordinate robot for material handling, transportation of heavy objects, etc. The cylindrical coordinate robot, having a first direct-acting or prismatic actuator disposed on a base for swivel motion and extending vertically of the robot and a second direct-acting actuator extending horizontally, is arranged to move the second actuator in the vertical direction by means of the first actuator, and drive an arm in the horizontal direction by the second actuator, so as to permit an end effector attached to the arm to perform various operations. Thus, the cylindrical coordinate robot has advantages such as high repeatability. However, the base thereof is large-sized, and the first actuator must be coupled to a drive mechanism accomodated in the base, so that the assembly, maintenance, and transportation of the robot require much labor, thus entailing higher costs, and requiring a wide robot installation space. Also, since the lower movement limit position of the second actuator is high, the range of action of the robot is narrow.